The Bilingual Brain

late learners benefit, too

Speaking a second language has many obvious practical advantages when it comes to communicating with the wider world. But the question of whether bilingualism confers consistent cognitive benefits, such as better memory or better problem-solving skills, is a topic of much discussion and debate in the fields of psychology and neuroscience. Some studies show distinct advantages, others not so much. But when we look at the effects of bilingualism on the structure of the brain itself, something is definitely going on. Moreover, learning a second language seems to help protect the brain as it ages.

In particular, studies involving people who learned a second language at a very young age show that long term bilingualism has an observable effect on the white matter in their brains. White matter plays an important role in transmitting signals between regions of the brain and within the central nervous system. Some researchers believe that structural changes in the white matter brought on by bilingualism may yield cognitive benefits by improving the connectivity between areas of the brain. There is also evidence that bilingualism helps to preserve the integrity of white matter in old age, and helps protect against cognitive decline. For example, bilingualism appears to delay the onset of Alzheimer’s disease by up to 5 years.

But is this limited to people who began speaking two or more languages at a very young age? In other words, is early-life neurological development an essential part of the picture?

Researchers at the University of Kent and the University of Reading have now shown that late learners can also glean similar benefits from bilingualism. And while the ‘late learners’ in this study began learning a second language relatively young (around 10 years old), it does demonstrate that the structural changes brought on by a second language can happen long after the early stage development of the brain.

There is a catch, though. It seems these changes to the brain, particularly the protection against age-related deterioration, are most likely due to a ‘continuous juggling’ of two (or more) languages. It’s this constant stimulation that helps to preserve the integrity of the white matter. So don’t just take that language course, you need to keep using the language regularly. And yes, this is an excellent reason for that immersion holiday in Provence. You’re welcome. De rien.